Grid for vacuum tubes



April 17, 1928.

G. H. PERRYMAN GRID FOR VACUUM TUBES Filed May 22. 1926 INVENTOR Z. Her-r yma/n/ B ORNEY 40 of Figure 1.

Patented Apr; 17, 1928:

onoaen H. PERBYMAN, or new "roan, 1v. Y.,- Assienoa rro rnnaman ntnc'rarc COMPANY, INC., OF NEW roan, n.1, A conroaa'rron or. new YORK.

eamron vacuum 'ronns.

' Application filed May 22,

This invention relates to a grid for vacuum tubes and has for its object to provide an article of this character which can be very cheaply made; which will be extremely 6 strong and rigid so that the possibility of the various parts shifting and changing the tube characteristics will be avoided.

It is wellknown that the type of vacuum tube grid in use at the present time consists of a spirally wound wire which isnot only diflicult to construct but requires careful workmanship with its attendant expense. Additionally, such type of grid always affords the possibility of the shifting of its parts with a resultant change in the tube characteristics. 1

My improved grid is formed from a single section of sheet metal by a stamping operation with the result that no great skill 0 is required to manufacture it and it can also be manufactured very economically. Furthermore it is of extremely strong and rigid constructlon, thus preventing shifting of its parts.

With these objects and such other objects as may hereinafter appear. in view, I have devised the particular arrangement of parts set forth below and more particularly ointed pointed out in the claim. appended ereto. I 7

Reference is to be had to the accompanym drawing, forming a part hereof, in which igure 1 is a plan view of my improved grid during the process of manufacture an showing the ribs in the same stamped out.

Figure 2 is a perspective view of one end of tlie partly finished grid disclosed in Figure Figure 3 is a sectional view on the line 3 Figure 4 is a longitudinal sectional view of a part of the finished grid.

Figure 5 is a perspective view of the finished grid; and

4a Figure 6 1s a plan view of the finished Throughout the various views of the drawings, similar reference characters designate similar parts.

In the embodiment of my invention dis-' closed in the accompanying drawing, 1 indicates the plate from which my improved grid is formed. This'plate consists of a section or piece of sheet metal of suitable thickness 1920. Serial No. 110,868.

are produced transversely of the strip-and simultaneously of the operation this mentio'ned, the longitudinal edges of the strip are curled in opposite to provide elongated continuous and 7 whichextend from one end 0 to the other and ceive and retain the grid-supporting wires 8 and 9 disclosed in Figure 5. I

The curlingor rolling of the longitudinal edges'bf the strip 1 acts also to stifl'en and reinforce the plate and prevent it from being distorted when a'subsequent operation dis-' roovesj 6 the plate torts outwardly theribs 3 as will be herein-.

after described.

A reference to Figures 4, 5 and 6 will showthat the next operation in the construction of the grid consists in bending outwardly in opposite directions the alternating ribs'so that a channel the reception of the tube filament in the or dinary manner.

It will further be seen that there are t'we 1 that is, those indicated at 10' and 6 and which arebent in series of ribs, in Flgures 4, 5

directions as at 4 and 5' is formed between them for which are intended to reone direction, and those which are indicated at '11 which are bent in the opposite'direction. When this operation has been-per formed, the grid is complete and the supporting wires 8 and 9 are welded in osition d in their respective grooves or channe s 6 and- 7 which extend along the longitudinal edges of the grid as was heretofore explained. It will be noted that each of the ribs 10 and 11 provided with a pair of bends as at 12 and 13, these bends being located adjacent I to the endsof the ribs near the points of ioinder of said ribs to the body of the plate.

The result of this construction-is thatthe resultant distorted ribs lie in parallelism to one. another and to the body 0 the plate.

It will be seen that through'the tion just described, an extremely strong grid is ing mainly of 11,- arev fixed t e outwardly bent ribs 10 and The entire grid is produced by a simple in position by their integral connection to the body of the grid and can the case with a spirally l construcrlgid and- 10o rovided. The parts, consistinvention, it is obvious that the stamping operation and thus can be made economically, greatly lessening. the cost of tube production.

Having described one embodiment of my same is not to be restricted thereto, but is broad enough to cover all structures scope of the annexed claim.

What I claim is:

An article of the class described consisting of a sheet metal plate provided with a plurality of spaced integral ribs. one series of said ribsbeing bent outwardly from the body of the plate, a second series of said ribs alternating with the first series and being bent outwardly in an opposite direccoming within thetion whereby a channel is provided between both series of ribs, each of the ribs of both series being provided with a pair of bends, with one bend located near each of the points of junction of each rib with the body of the plate whereby both series of ribs lie in substantial parallelism with each other and with the body of the plate, and the longitudinal side edges of the body of the plate being curled in reverse directions for their entire length to provide grooves for the reception of supporting wires.

Signed at the city, county and State of New York, this 19th day ofMay, 1926,

e. n; PERRYMAN. 

